OK another one of my hare brained ideas is to recast all the defender body panels in carbon fiber. I am going to be ramping up for some serious vacuum bagging next summer for boat projects and I thought as long as I'm at it, make some molds for the front clip, doors and maybe some other parts. These can then be reproduced in regular old gel coat/glass/epoxy or carbon fiber/epoxy. If anyone has some interest or input on this, let me know. (I also need a willing donor who would allow me to cast the molds)

I want to make sliders and front and rear bumpers for my 03 HSE out of carbon fiber. Steel would be too heavy and it would be hard to maintain the lines of the truck. CF would be strong and light and I do not think it would reduce the value of the truck but actually increase it.

The advantage of the plastic parts is that they are resilient and more likely to deform and spring back instead of dent, crumple or bend.
Making a bulkhead would probably be the least troublesome from the aspect of it being done up from flat pieces that are glued together with resin and cloth. Awfully labor intensive, but would yield a very nice product I think.

I want to make sliders and front and rear bumpers for my 03 HSE out of carbon fiber. Steel would be too heavy and it would be hard to maintain the lines of the truck. CF would be strong and light and I do not think it would reduce the value of the truck but actually increase it.

Any thoughts?

This sort of thing is very easy to do. You build a shaped core out of blue foam from the Home Depot and more or less wrap it in CF. You'll want very rounded shape to make it easy for the cloth wrap to conform. My method would be to use 6 inch tape and wrap it dry with alternating directions and then wet it out with System 3 or West epoxy. Vacuum bagging will deliver a very smooth surface that is slightly nubby from the peel ply. You wouldn't HAVE to vacuum bag it of course. You may also use layers of regular glass cloth to build up thickness and use the CF as a final layer. Vacuum pumps can be rented for a day or two at a very low cost. Vacuum bagging supplies are available on line from Jamestown Distributors.

Carbon fiber composites are far stronger than steel parts of equal thickness. A 1/4 inch skid plate of carbon fiber composite will take far more punishment than a similar steel part. A carbon fiber wing panel will not break or bend. It may scratch, but probably never actually fail.

Follow-up Post:

Quote:

Originally Posted by landrovered

Don't you need an autoclave to do CF properly?

only for pre preg, in which the resin is already infused in the cloth and requires heat to form a bond. Regular old dry CF cloth is used with common epoxy resins.

While we are having this conversation, what would you suggest for CF strengthening of fiberglass? Could you lay the layers of CF on the interior of the fiberglass and then vacuum it to add strength?

The latest shiz is something called resin infusion. In this process, all the layers are assembled dry. This way you can orient all the stuff exactly right without having to fuss with shifting wet layers. Once you make the layers, you apply the vacuum bagging layers of peel ply, breather blanket and bagging film. A special thin viscosity resin is sucked in when the vacuum is drawn which gets into every micropore of the matrix. Gives a strong consistent part every time. Best for making hat channel and stuff like that.

To answer your question, CF Is really best for parts that are long and thin like foils, blades, spars, wings, and struts. It would be used on a Rover quite nicely on rock sliders to give more strength longitudinally. A sandwich of CF inside a wrapper of e glass and resin will likely be the best overall, but the aesthetic of the CF will be buried inside the part.

Follow-up Post:

Quote:

Originally Posted by thewap

I could definitely envision CF body panels -roof-wings-doors etc, but sliders? CF has great impact resistance but abrasion resistance such as sliding on rocks?

The abrasion resistance comes mainly from the epoxy resin. Assuming a proper layup of the glass/epoxy, abrasion resistance will be quite good. What happens is the material gouges, but the lamination does not come apart. Worst case, you just add another layer of cloth over the gouged out area and build the thickness back up again.

I've seen LOTS of broken carbon fiber stuff. Carbon fiber stronger than steel just based on thickness? You can't even discuss that comparison without laying down some other parameters. What is strength? it is merely a catch all word used to describe a number of differing material qualities. Are we talking tensile strength, shear, compressive, modulus of elasticity, or what? Maybe pound for pound but sorry dropping a 3 ton truck on a 1/4" thick hollow CF slider onto a single point load of immovable rock the rock is going to win every time. Carbon fiber is not renowned for its impact resistance so much as its rigidity to weight ratio. Great for boat hulls and bicycle frames and other components (brake levers, cranks, forks, etc) but worth sod f***ing all for impact resistance.

Not to mention the time involved and the cost. You want to spend the rest of your days laying up carbon fiber bulkheads or do you actually want to drive a vehicle. Ron's Canadian loctite is a btter answer to that problem. Heavier, yes. This ain't the Tour De France or the America's Cup. We have intenral combustion engines to pull our heavy asses around

You can have it strong, light and cheap...pick any two. It can be built well, built fast, and built cheap...again...pick any two...

Quote:

Originally Posted by o2batsea

Carbon fiber composites are far stronger than steel parts of equal thickness. A 1/4 inch skid plate of carbon fiber composite will take far more punishment than a similar steel part. A carbon fiber wing panel will not break or bend. It may scratch, but probably never actually fail.

Hmm. Don't know about a carbon fiber bulkhead. Maybe it would work if the areas that actually show have the carbon fiber as the top layer, but the actual structural bits done with a more traditional glass layup and painted a similar dark gray. One problem with exposed carbon fiber is that the epoxy resins are affected by UV which can degrade them, turn them yellow and weaken the part. If the parts were clear coated with something that has UV inhibitors it might make it less susceptible to that kind of degradation.
There's probably an ideal plastic out there that would be just the ticket. Most likely a thermoset sheet that you vacuum form like a hot tub. That and a nice robot to water jet all the cuts, holes and trimming needed. And a robot plastic welder to assemble the parts.
I mean Dave has a point in that the development of a new set of body panels in plastic, while having a great appeal, is probably not a job for the shade tree set like your humble author. I would surely be happier out on the boat than futzing with mold making. See, I told you it was hare brained.

I want to make sliders and front and rear bumpers for my 03 HSE out of carbon fiber. Steel would be too heavy and it would be hard to maintain the lines of the truck. CF would be strong and light and I do not think it would reduce the value of the truck but actually increase it.

Any thoughts?

Scott, what about Denny making a special order for the 03 ?
You have enough HP to move the the added weight.
I'm pretty sure HLC can make something really nice.

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Scott, what about Denny making a special order for the 03 ?
You have enough HP to move the the added weight.
I'm pretty sure HLC can make something really nice.

We have discussed it and he would love nothing more but I really like the curves of the 03 the way they are and would like to do something that would be a "next generation" mod and push the technological envelope. We are going to have to move to lighter materials in the future if our sport is going to survive the next 25 years. They built battleships at the turn of the last century, we know we can do that, I want to do something befitting the 21st century.